In a conventional resonant type high frequency power supply device shown in FIG. 15, a high frequency FET (Field Effect Transistor) for RF (Radio Frequency) is used as a power element Q1. Then, a drive circuit of transformer type 101 and an RF power amplifier circuit 102 are used to drive this high frequency FET, and a multi-output type power supply circuit 103 is further used to drive the RF power amplifier circuit 102 (for example, refer to non-patent reference 1).